1. Technical Field
This application relates to a vascular device and more particularly to a vascular device for capturing embolic material during surgical procedures.
2. Background of Related Art
During vascular surgical procedures such as stenting, angioplasty, thrombectomy, and atherectomy, embolic material such as plaque and blood clots can become dislodged. Dislodgement of such embolic material can cause the emboli to flow downstream to lodge in the vascular system, thereby occluding the flow of oxygenated blood to the brain or other vital organs. Such occlusion can compromise peripheral circulation resulting in amputation, or result in heart attack, stroke or even death.
Techniques to cut the debris into smaller sizes, such as by use of lasers, have had significant drawbacks, such as the inability to ensure all the debris is cut into sufficiently small fragments. If some of the fragments remain too large, then occlusion of the vessels can occur causing the problems and risks enumerated above.
Attempts have been made to place a device distal (downstream) of the stenosis, thrombus, etc. to capture the emboli. Such distal protection devices typically are collapsible for insertion and expandable once in the vessel. Some devices are in the form of an expandable balloon which is inserted within the vessel inside a sheath. When the sheath is withdrawn, the balloon is expanded to block emboli. These balloon devices even in the collapsed position increase the profile of the device since they are wrapped on the outside of the device. In other distal protection devices, a wire is covered by a membrane. These wires extend laterally from the device and may not enable the membrane to block the entire region of the vessel. Failure to expand to a geometry to block the entire region can result in the unwanted passage of debris which can cause vessel occlusion and the aforementioned adverse consequences.
The need therefore exists for an improved distal protection device. Such device would have a reduced profile to facilitate insertion and to better enable placement of the device distal of the emboli to block potential downstream flow. The device would also be easy to manipulate and sufficiently fill the vessel area to ensure all passage is blocked. The device would further be configured to avoid unwanted collapse during use.
It would also be desirable to provide a distal protection device which meets the above criteria plus has the advantage of accommodating various sized blood vessels. There is a tradeoff between providing large expansion of a distal protection device to block large blood vessels while ensuring that such large expansion would not damage a small blood vessel. Therefore, it would be advantageous to provide a single device which can expand sufficiently to effectively block embolic material without damaging the vessel, thus avoiding having to use different devices to accommodate different vessel sizes.